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We report on early results from a pilot program searching for metal-poorstars with LAMOST and follow-up high-resolution observation acquired with theMIKE spectrograph attached to the Magellan~II telescope. We performed detailedabundance analysis for eight objects with iron abundances [Fe/H] < -2.0,including five extremely metal-poor (EMP; [Fe/H] < -3.0) stars with two having[Fe/H] < -3.5. Among these objects, three are newly discovered EMP stars, oneof which is confirmed for the first time with high-resolution spectralobservations. Three program stars are regarded as carbon-enhanced metal-poor(CEMP) stars, including two stars with no enhancement in their neutron-captureelements, which thus possibly belong to the class of CEMP-no stars; one ofthese objects also exhibits significant enhancement in nitrogen, and is thus apotential carbon and nitrogen-enhanced metal-poor star. The [X/Fe] ratios ofthe sample stars generally agree with those reported in the literature forother metal-poor stars in the same [Fe/H] range. We also compared the abundancepatterns of individual program stars with the average abundance pattern ofmetal-poor stars, and find only one chemically peculiar object with abundancesof at least two elements (other than C and N) showing deviations larger than0.5dex. The distribution of [Sr/Ba] versus [Ba/H] agrees that an additionalnucleosynthesis mechanism is needed aside from a single r-process. Two programstars with extremely low abundances of Sr and Ba support the prospect that bothmain and weak r-process may have operated during the early phase of Galacticchemical evolution. The distribution of [C/N] shows that there are two groupsof carbon-normal giants with different degrees of mixing. However, it isdifficult to explain the observed behavior of the [C/N] of thenitrogen-enhanced unevolved stars based on current data.

Spectroscopic analysis of metal-poor stars from LAMOST: early results